Thank you so much.
So can I just pick up the arm hole stitches and knit a sleeve from the shoulder down, knitting in the round with double points?
Or..should I NOT stitch up the shoulder seam and pick up the stitches with straight needles and knit from the arm hole stitches down to the cuff?
My sweater now looks like a sleeveless sweater. I mean, I knit it all in the round and divided for the arm holes and top part, then I stitched up the front and back shoulder seams, but I can easily take out the stitches on the shoulder seams so the arm holes are not in a circle yet.